PSO粒子群算法解决旅行商问题的MATLAB源码

%Á£×ÓȺËã·¨Çó½âÂÃÐÐÉÌÎÊÌâ%BylReijcloseall;clearall;PopSize=500;%ÖÖȺ´óСCityNum=14;%³ÇÊÐÊýOldBestFitness=0;%¾ÉµÄ×îÓÅÊÊÓ¦¶ÈÖµIteration=0;%µü´ú´ÎÊýMaxIteration=2000;%×î´óµü´ú´ÎÊýIsStop=0;%³ÌÐòÍ£Ö¹±êÖ¾Num=0;%È¡µÃÏàͬÊÊÓ¦¶ÈÖµµÄµü´ú´ÎÊýc1=0.5;%ÈÏ֪ϵÊýc2=0.7;%Éç»áѧϰϵÊýw=0.96-Iteration/MaxIteration;%¹ßÐÔϵÊý,Ëæµü´ú´ÎÊýÔö¼Ó¶øµÝ¼õ%½Úµã×ø±ênode=[16.4796.10;16.4794.44;20.0992.54;22.3993.37;25.2397.24;...22.0096.05;20.4797.02;17.2096.29;16.3097.38;14.0598.12;...16.5397.38;21.5295.59;19.4197.13;20.0994.55];%³õʼ»¯¸÷Á£×Ó£¬¼´²úÉú·¾¶ÖÖȺGroup=ones(CityNum,PopSize);fori=1:PopSizeGroup(:,i)=randperm(CityNum)';endGroup=Arrange(Group);%³õʼ»¯Á£×ÓËٶȣ¨¼´½»»»Ðò£©Velocity=zeros(CityNum,PopSize);fori=1:PopSizeVelocity(:,i)=round(rand(1,CityNum)'*CityNum);%roundÈ¡Õûend%¼ÆËãÿ¸ö³ÇÊÐÖ®¼äµÄ¾àÀëCityBetweenDistance=zeros(CityNum,CityNum);fori=1:CityNumforj=1:CityNumCityBetweenDistance(i,j)=sqrt((node(i,1)-node(j,1))^2+(node(i,2)-node(j,2))^2);endend%¼ÆËãÿÌõ·¾¶µÄ¾àÀëfori=1:PopSizeEachPathDis(i)=PathDistance(Group(:,i)',CityBetweenDistance);endIndivdualBest=Group;%¼Ç¼¸÷Á£×ӵĸöÌ弫ֵµãλÖÃ,¼´¸öÌåÕÒµ½µÄ×î¶Ì·¾¶IndivdualBestFitness=EachPathDis;%¼Ç¼×î¼ÑÊÊÓ¦¶ÈÖµ,¼´¸öÌåÕÒµ½µÄ×î¶Ì·¾¶µÄ³¤¶È[GlobalBestFitness,index]=min(EachPathDis);%ÕÒ³öÈ«¾Ö×îÓÅÖµºÍÏàÓ¦ÐòºÅ%³õʼËæ»ú½âfigure;subplot(2,2,1);PathPlot(node,CityNum,index,IndivdualBest);title('Ëæ»ú½â');%Ñ°ÓÅwhile(IsStop==0)&(IterationMaxIteration)%µü´ú´ÎÊýµÝÔöIteration=Iteration+1;%¸üÐÂÈ«¾Ö¼«ÖµµãλÖÃ,ÕâÀïָ·¾¶fori=1:PopSizeGlobalBest(:,i)=Group(:,index);end%Çópij-xij,pgj-xij½»»»Ðò£¬²¢ÒÔ¸ÅÂÊc1£¬c2µÄ±£Áô½»»»Ðòpij_xij=GenerateChangeNums(Group,IndivdualBest);pij_xij=HoldByOdds(pij_xij,c1);pgj_xij=GenerateChangeNums(Group,GlobalBest);pgj_xij=HoldByOdds(pgj_xij,c2);%ÒÔ¸ÅÂÊw±£ÁôÉÏÒ»´ú½»»»ÐòVelocity=HoldByOdds(Velocity,w);Group=PathExchange(Group,Velocity);%¸ù¾Ý½»»»Ðò½øÐз¾¶½»»»Group=PathExchange(Group,pij_xij);Group=PathExchange(Group,pgj_xij);fori=1:PopSize%¸üи÷·¾¶×ܾàÀëEachPathDis(i)=PathDistance(Group(:,i)',CityBetweenDistance);endIsChange=EachPathDisIndivdualBestFitness;%¸üкóµÄ¾àÀëÓÅÓÚ¸üÐÂÇ°µÄ£¬¼Ç¼ÐòºÅIndivdualBest(:,find(IsChange))=Group(:,find(IsChange));%¸üиöÌå×î¼Ñ·¾¶IndivdualBestFitness=IndivdualBestFitness.*(~IsChange)+EachPathDis.*IsChange;%¸üиöÌå×î¼Ñ·¾¶¾àÀë[GlobalBestFitness,index]=min(EachPathDis);%¸üÐÂÈ«¾Ö×î¼Ñ·¾¶,¼Ç¼ÏàÓ¦µÄÐòºÅifGlobalBestFitness==OldBestFitness%±È½Ï¸üÐÂÇ°ºÍ¸üкóµÄÊÊÓ¦¶ÈÖµ;Num=Num+1;%ÏàµÈʱ¼Ç¼¼ÓÒ»;elseOldBestFitness=GlobalBestFitness;%²»ÏàµÈʱ¸üÐÂÊÊÓ¦¶ÈÖµ£¬²¢¼Ç¼ÇåÁã;Num=0;endifNum=20%¶à´Îµü´úµÄÊÊÓ¦¶ÈÖµÏà½üʱ³ÌÐòÍ£Ö¹IsStop=1;endBestFitness(Iteration)=GlobalBestFitness;%ÿһ´úµÄ×îÓÅÊÊÓ¦¶Èend%×îÓŽâsubplot(2,2,2);PathPlot(node,CityNum,index,IndivdualBest);title('ÓÅ»¯½â');%½ø»¯ÇúÏßsubplot(2,2,3);plot((1:Iteration),BestFitness(1:Iteration));gridon;title('½ø»¯ÇúÏß');%×îС·¾¶ÖµGlobalBestFitnessfunctionGroup=Arrange(Group)[xy]=size(Group);[NO1,index]=min(Group',[],2);%ÕÒµ½×îСֵ1fori=1:ypop=Group(:,i);temp1=pop([1:index(i)-1]);temp2=pop([index(i):x]);Group(:,i)=[temp2'temp1']';endfunctionChangeNums=GenerateChangeNums(Group,BestVar);[xy]=size(Group);ChangeNums=zeros(x,y);fori=1:ypop=BestVar(:,i);%´ÓBestVarÈ¡³öÒ»¸ö˳Ðòpop1=Group(:,i);%´ÓÁ£×ÓȺÖÐÈ¡³ö¶ÔÓ¦µÄ˳Ðòforj=1:x%´ÓBestVarµÄ˳ÐòÖÐÈ¡³öÒ»¸öÐòºÅNoFromBestVar=pop(j);fork=1:x%´Ó¶ÔÓ¦µÄÁ£×Ó˳ÐòÖÐÈ¡³öÒ»¸öÐòºÅNoFromGroup=pop1(k);if(NoFromBestVar==NoFromGroup)&&(j~=k)%Á½ÐòºÅͬÇÒ²»ÔÚͬһλÖÃChangeNums(j,i)=k;%½»»»×Ópop1(k)=pop1(j);pop1(j)=NoFromGroup;endendendendfunctionHold=HoldByOdds(Hold,Odds)[x,y]=size(Hold);fori=1:xforj=1:yifrandOddsHold(i,j)=0;endendendfunctionSumDistance=PathDistance(path,CityBetweenDistance)L=length(path);%pathΪһ¸öÑ­»·µÄ½Úµã˳ÐòSumDistance=0;fori=1:L-1SumDistance=SumDistance+CityBetweenDistance(path(i),path(i+1));endSumDistance=SumDistance+CityBetweenDistance(path(1),path(L));%¼ÓÉÏÊ×β½ÚµãµÄ¾àÀëfunctionGroup=PathExchange(Group,Index)[xy]=size(Group);fori=1:ya=Index(:,i);%È¡³öÆäÖÐÒ»×é½»»»Ðòpop=Group(:,i);%È¡³ö¶ÔÓ¦µÄÁ£×Óforj=1:x%È¡³öÆäÖÐÒ»¸ö½»»»Ëã×Ó×÷½»»»ifa(j)~=0pop1=pop(j);pop(j)=pop(a(j));pop(a(j))=pop1;endendGroup(:,i)=pop;endfunctionPathPlot(node,CityNum,index,EachBest);fori=1:CityNumNowBest(i,:)=node((EachBest(i,index)),:);endNowBest(CityNum+1,:)=NowBest(1,:);plot(node(:,1),node(:,2),'*');line(NowBest(:,1),NowBest(:,2));gridon;